v3.3.1.900
Document and Entity Information Document - USD ($)
$ in Billions
12 Months Ended
Dec. 31, 2015
Feb. 12, 2016
Jun. 30, 2015
Document And Entity Information [Abstract]      
Entity Registrant Name VERISIGN INC/CA    
Entity Central Index Key 0001014473    
Current Fiscal Year End Date --12-31    
Entity Filer Category Large Accelerated Filer    
Document Type 10-K    
Document Period End Date Dec. 31, 2015    
Document Fiscal Year Focus 2015    
Document Fiscal Period Focus FY    
Amendment Flag false    
Entity Common Stock, Shares Outstanding   109,468,547  
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Public Float     $ 3.0